Polyimides are useful as components which require excellent thermal, electrical and/or mechanical properties. For general discussion of polyimides preparation, characterization and applications see Polyimides, Synthesis, Characterization and Applications, K. L. Mittal, ed Plenum, N.Y. 1984.
Polyimides based on pyromellitic dianhydride and various organic diamines are disclosed in U.S. Pat. No. 4,485,140 to Gannett et al (E. I. DuPont de Nemours and Co.).
Polyimides based on diamines such as 2,2'-di-(p-aminophenyloxy)diphenyl and various dianhydrides are disclosed in U.S. Pat. No. 4,239,880 to Darms (Ciba-Geigy Corp.).
Harris et al. in U.S. patent application Ser. No. 07/315,327, has disclosed the preparation of soluble polyimides based on polyphenylated diamines. The polyimides taught in this reference are typically rod like polyimides and possess little if any thermoplastic properties.
Numerous patents deal with the manufacture of composites utilizing carbon fibers or other similar fibrous reinforcing agent with polyimides.
In U.S. Pat. No. 4,851,280, Gupta teaches the use of carbon fiber reinforced polyimide composites for fabricating tools. Gupta teaches the use of a different class of polyimides than those employed in the present invention.
In U.S. Pat. No. 4,395,514, Edelman teaches a process for the preparation of polyimide composites including carbon fiber reinforced polyimide composites. The main thrust of the Edelman patent is the use of a class of cyclic peroxyketal catalysts. Edelman teaches the use of divalent aryl radicals.
In U.S. Pat. No. 4,578,470, Webb teaches that transimidization can be used as a mode of propagation in the preparation of polyimides. However, the use of transimidization to aid in the processing of copolyimides is not disclosed. Diamines that undergo transimidization are also not disclosed. In Webb, transimidization only occurs at the growing chain ends.
None of the above composite patents teach or insinuate that the copolyimides or copolyimide composites of the present invention would have the unusual properties necessary.